Climate, fire and vegetation dynamics are often tightly coupled through time. Here, we use a 14 kyr sedimentary charcoal and pollen record from Lake Osborne, Tasmania, Australia, to explore how this relationship changes under varying climatic regimes within a temperate rainforest ecosystem. Superposed epoch analysis reveals a significant relationship between fire and vegetation change throughout the Holocene at our site. Our data indicates an initial resilience of the rainforest system to fire under a stable cool and humid climate regime between ca. 12-6 ka. In contrast, fires that occurred after 6 ka, under an increasingly variable climate regime wrought by the onset of the El Niño-Southern Oscillation (ENSO), resulted in a series of changes within the local rainforest vegetation that culminated in the replacement of rainforest by fire-promoted Eucalypt forest. We suggest that an increasingly variable ENSO-influenced climate regime inhibited rainforest recovery from fire because of slower growth, reduced fecundity and increased fire frequency, thus contributing to the eventual collapse of the rainforest system.

Item Type:	Refereed Article
Keywords:	pollen, charcoal, rainforest, Tasmania, El Nino-Southern Oscillation (ENSO), superposed epoch analysis (SEA)
Research Division:	Earth Sciences
Research Group:	Physical geography and environmental geoscience
Research Field:	Palaeoclimatology
Objective Division:	Environmental Policy, Climate Change and Natural Hazards
Objective Group:	Understanding climate change
Objective Field:	Effects of climate change on Australia (excl. social impacts)
UTAS Author:	Bowman, DMJS (Professor David Bowman)
ID Code:	129088
Year Published:	2018
Web of Science® Times Cited:	14
Deposited By:	Plant Science
Deposited On:	2018-11-08
Last Modified:	2019-03-27
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